Seems like the start of a good idea. Adding to Mourn's thoughts, though;

There's some physical engineering issues here. While gravity can be mitigated underwater, you appear to be cantilevering everything off the elevator shaft, and this is... difficult. Water moves, alot, and it will cause large pods 'hanging' off of structures to sway - and eventually snap. But that can be dealt with easily enough with a little bit of knowhow, and if no one in your group has the knowhow, it doesn't matter much for versimilitude anyway.

The bigger problem I see, though, is really one of scale. This is an expensive facility, and very small. Basically, to be worth it, it has to be a supermax, and then some, but it just doesn't seem to have that. You have provisions for 125 prisoners - and no provisions for the 500 guards, who can't possibly be commuting home every shift. Even with half the guards on the payroll ashore at a time, that's one inmate per 2 guards on shift - with 2-3 days off a week for the guards. Everything has to be shipped in and out, probably daily to weekly. Power has to be generated out there. Every prisoner will cost millions per year - and silver ore can run as low as $100 a ton, depending on how rich it is.

This is not a prison for "Terrorists and War Criminals", this is a prison for Adolph.

This is definitely a semi secure prison. However it bespeaks of one in a movie i saw once. With the exception of the mining area it is near identicle.

The size of the rooms seem off to me as well a ten by ten room is not a normal sized room for two inmates to be considered cramped. Most of the rooms I've delt with (I worked in the prison system not a member) were eight by ten and those were considered very large for two people. Five by eight were common.

The idea of the inmates in solitary having weights is a very bad idea. Assuming there are facilities for them to use the bathroom what is stopping them from flooding the rooms and then using the weights as weapons? Also having the kitchen on the solitary level also is dangerous if the kitchen is run by the inmates. It should be on the top level away from inmate living quarters. Even though knives are not allowed it is a functioning kitchen and there are a lot of utensils that can be used or fashioned into makeshift weapons. Rolling pin anyone?

All that being said, there are more I will just slow down on the harsh critique, this also has some ideas to pull from. Making the inmates work 750 feet under the water is an interesting idea. The can run but where? Without a breathing apparatus they would drown before getting to the surface. Also making the inmates responsible for pumping air into the prison is interesting.

I don't find this a bad sub but I just don't find enough draw to it for me to make it say Whoa! It's a prison and underwater. Cool but it's been done. Add some plot hooks or some NPC personalities to make it stand out and it may just do it for me.

Another thing I thought of, since the entire complex is run off of 14 hour batteries that are charged daily by inmate power... what happens during a huge storm? Say a four or five day hurricane plows through the area. it will be impossible to throw the inmates on the roof of this floating bobber to withstand 75 mile and hour winds, if your lucky, to be able to recharge the generator that will only last for 14 hours which takes ten hours to fiully charge the air supply and generator. I agree with Siren that this complex is far to small to be cost efficient even in a magical fantasy world where we can get magic to do for us that manual labor couldnt. Just another observation.

This is a good start. When reading this, I thought of about a dozen questions that I would want answered if I was a PC in this environment. Here are a few:

1. Emergency procedures. What happens in the event of a natural disaster, hull breach etc? Are the prisoners left to drown, or would there be an opportunity to escape?

2. The elevator can't really be the only way to move between levels, right? Otherwise, what happens when the power goes out?

3. If 5 of the maximum security cells are occupied, it'd be neat to have a list of those inmates' names and what they were in for. Are they gang leaders? I bet there are lots of stories/legends circulating about them on the prison floor, so having that info would be nice.

Loose lips sink ships. In this case, loose security. I like the thought of a hit database but the way it is described it pretty much lets anybody view any job, take a look, and decide if they want to take it. Way too much information available without commitment. Pay drops aren't very trustworthy either unless you have some kind of failsafe to ensure payment and/or action on the job.

I think this is a nice solid idea, I would have made it a Location submission, located in Cyberspace, as it is not really a plot as it is a place to find plot. It you gave us a short story about finding the web page, discovering some sort of plot, then trying to shut down the page, it could be a very nice plot. But as is, it's not bad.

I like the idea however. If your able to hack into the site and in the unfortunate event see your name or the name of someone you know, how would it not also be possible to change the category under your name to completed so no one would come find you? Fairly easy if you ask me if they can hack the site.